Cu/Zn-superoxide dismutase (Cu/Zn-SOD) is an enzyme that is ubiquitously present in the cytoplasm and causes dismutation of superoxide radicals, therefore Cu/Zn-SOD is primarily used as an antioxidant marker. Levels o...Cu/Zn-superoxide dismutase (Cu/Zn-SOD) is an enzyme that is ubiquitously present in the cytoplasm and causes dismutation of superoxide radicals, therefore Cu/Zn-SOD is primarily used as an antioxidant marker. Levels of Cu/Zn-SOD are higher in the serum of hemodialysis patients than in serum of healthy volunteers. The increase of serum Cu/Zn-SOD levels is related to the decrease of kidney function with aging and arteriosclerosis in hemodialysis patients. Moreover, infection, vascular puncture, and hemostasis may be related to the increase in serum Cu/Zn-SOD levels. As it is associated with numerous factors in hemodialysis patients, Cu/Zn-SOD may serve as a complex marker for arteriosclerosis, vascular, and inflammatory conditions. It is important to investigate various agents that decrease serum Cu/Zn-SOD levels to improve the life-span of hemodialysis patients.展开更多
AIM: To investigate the effects of hydrogen(H2) on Cu, Zn superoxide dismutase(SOD1) activation in a rat model of corneal alkali burn. METHODS: In each rat, one cornea was subjected to alkali exposure. Physiological s...AIM: To investigate the effects of hydrogen(H2) on Cu, Zn superoxide dismutase(SOD1) activation in a rat model of corneal alkali burn. METHODS: In each rat, one cornea was subjected to alkali exposure. Physiological saline(saline group) or H2-dissolved saline(H2 group) was instilled continuously on the cornea for 5 min before and after alkali exposure. Inflammatory cells, neovascularization, and cytoplasmic SOD1 levels were evaluated immunohistochemically in enucleated eyes from both groups. Three-dimensional ultrastructural tissue changes in the eyes were analyzed using low-vacuum scanning electron microscopy.RESULTS: The numbers of both inflammatory and vascular endothelial cells were significantly reduced in the corneas of the H2 group(P<0.01). Furthermore, H2 treatment increased both cytoplasmic SOD1 levels(P<0.01) and activity in corneal epithelial cells(P<0.01). Notably, the SOD1 activity level in the H2 group was approximately 2.5-fold greater than that in the saline group.CONCLUSION: H2 treatment suppresses inflammation and neovascularization in the injured cornea and indirectly suppresses oxidative insult to the cornea by upregulating the SOD1 enzyme protein level and activity.展开更多
Objective:To determine the activity of superoxide dismutase(SOD) in the male and female haematophagous caprine worms,Haemonchus contortus infecting Capra hircus,and their E/S products and also to analyse the effect of...Objective:To determine the activity of superoxide dismutase(SOD) in the male and female haematophagous caprine worms,Haemonchus contortus infecting Capra hircus,and their E/S products and also to analyse the effect of Haemonchus infection on the level of host SOD.Methods:The SOD activity was analysed by using the pyrogallol autoxidation assay and non-denaturing polyacrylamide gel electrophoresis followed by specific enzyme staining by riboflavin-nitroblue tetrazolium method.Results:The adult females were found to have higher enzyme activity than the male worms.Appreciable amount of SOD activity was also detected in the worm culture medium and female worms secreted more SOD in comparison to the male parasites.The SOD activity was negatively correlated to the worm burden.Statistically significant decrease in SOD activity(P<0.05) was observed in the heavily infected host tissue in comparison to the control non-infected host tissue.SOD profile of the crude extracts of both the sexes revealed polymorphism and a fast migrating activity band being characteristic of E/S products.The SOD activities were found highly sensitive to potassium cyanide indicating the Cu/Zn form of SOD.Conclusions:Haemonchus contortus is a key model parasite for drug and vaccine discovery.The presences of SOD activity in appreciable amount in the parasite as well as its E/S products indicate that it has a well-developed active antioxidant system to protect itself from the host immune attack.SOD could be the target for vaccine development which is the need of the hour as mass drug administration for parasite control has resulted in anthelmintic resistance across the globe and threatens the viability of sheep and goat industry in many regions of the world.The infection with Haemonchus causes a drastic reduction in SOD activity of the host tissue thus effecting its protective potential.One characteristic SOD band was found in the females which was not present in any other preparations and thus could be exploited for further studies on diagnostic/control measures.展开更多
The expression of a rice Cu/Zn superoxide dismutase （Cu/Zn-SOD） in Saccharomyces cerevisiae regulated by GAPDH promoter, involved in the inhibition of endogenous Glutathione （GSH） synthesis, and the competitive ex...The expression of a rice Cu/Zn superoxide dismutase （Cu/Zn-SOD） in Saccharomyces cerevisiae regulated by GAPDH promoter, involved in the inhibition of endogenous Glutathione （GSH） synthesis, and the competitive expression was detected by constructing the expression vector transferred Cu/Zn-SOD gene into wild-type S. cerevisiae. Transcription and expression of the Cu/Zn-SOD gene in S. cerevisiawere were confirmed by northern blot and SDS-PAGE, respectively, and activity of the Cu/Zn-SOD from crude extracts was enzymatically detected based on the effect of nitroblue tetrazolium （NBT） after running a native polyacrylamide gel. The GSH synthesis was also tested by DTNB （5, 5＇-Dithiobis （2-nitrobenzoic acid）） method. Results showed that GSH synthesis was evidently suppressed by the expression of Cu/Zn-SOD gene in both control and heat shock strains. It implied that the expression of the Cu/Zn-SOD gene in S. cerevisiae has more potential facility in response to oxidative exposure than that of endogenous GSH, although Cu/Zn-SOD and GSH were both contributed to the function of oxygen radical oxidoreduction.展开更多
Amyotrophic lateral sclerosis(ALS)is characterized by adult-onset progressive degeneration of upper and lower motor neurons.Increasing numbers of genes are found to be associated with ALS;among those,the first identif...Amyotrophic lateral sclerosis(ALS)is characterized by adult-onset progressive degeneration of upper and lower motor neurons.Increasing numbers of genes are found to be associated with ALS;among those,the first identified gene,SOD1 coding a Cu/Zn-superoxide dismutase protein(SOD1),has been regarded as the gold standard in the research on a pathomechanism of ALS.Abnormal accumulation of misfolded SOD1 in affected spinal motor neurons has been established as a pathological hallmark of ALS caused by mutations in SOD1(SOD1-ALS).Nonetheless,the involvement of wild-type SOD1 remains quite controversial in the pathology of ALS with no SOD1 mutations(non-SOD1 ALS),which occupies more than 90%of total ALS cases.In vitro studies have revealed post-translationally controlled misfolding and aggregation of wild-type as well as of mutant SOD1 proteins;therefore,SOD1 proteins could be a therapeutic target not only in SOD1-ALS but also in more prevailing cases,non-SOD1 ALS.In order to search for evidence on misfolding and aggregation of wild-type SOD1 in vivo,we reviewed pathological studies using mouse models and patients and then summarized arguments for and against possible involvement of wild-type SOD1 in non-SOD1 ALS as well as in SOD1-ALS.展开更多
To investigate whether the proton-accepting ability of imidazole in Cu,Zn-superoxide dismutase （SOD） was possibly modulated by Zn（Ⅱ） or not, the proton affinity （Ap） of N^3 in imidazole group was calculated by ...To investigate whether the proton-accepting ability of imidazole in Cu,Zn-superoxide dismutase （SOD） was possibly modulated by Zn（Ⅱ） or not, the proton affinity （Ap） of N^3 in imidazole group was calculated by density functional theory （DFT） with B3LYP functional. It was found that Zn（Ⅱ） attenuates the Ap, because of its electron-withdrawing effect, while the three ligands connected with Zn（Ⅱ） （residues of two His and one Asp） exert an opposite effect, owing to their electron-donating ability. This finding suggested that the three ligands should play a role in the normal function of Cu,Zn-SOD and should be taken into consideration in the future study.展开更多
When a protein is encapsulated into poly( DL -lactide-co-glycolide)(PLGA) microspheres by means of the double-emulsion method,the harsh microspheres formation process including ultrasonification,exposure to an organic...When a protein is encapsulated into poly( DL -lactide-co-glycolide)(PLGA) microspheres by means of the double-emulsion method,the harsh microspheres formation process including ultrasonification,exposure to an organic solvent and a polymer may cause the denaturation of the protein. In this study,we investigated the enzymatic activity change and the effect of the excipients on the stability of recombinant human Cu,Zn-superoxide dismutase(rhCu,Zn-SOD) during the emulsification. The specific activity recovery was found to be concentration dependent and the excipients involved such as PEG 600 and Tween 20,and trehalose were shown to increase the stability of rhCu,Zn-SOD. The protein structural integrity within the microspheres was analyzed by FTIR. The structure of rhCu,Zn-SOD within PLGA microspheres containing trehalose was found to be similar to that of the native solid state,whereas the protein encapsulated during the preparation in the absence of any excipient changed due to the possible hydrophobic interaction with the polymer. The results suggest that a rational stability strategy for protein to be encapsulated into microspheres should aim at different processes.展开更多
文摘Cu/Zn-superoxide dismutase (Cu/Zn-SOD) is an enzyme that is ubiquitously present in the cytoplasm and causes dismutation of superoxide radicals, therefore Cu/Zn-SOD is primarily used as an antioxidant marker. Levels of Cu/Zn-SOD are higher in the serum of hemodialysis patients than in serum of healthy volunteers. The increase of serum Cu/Zn-SOD levels is related to the decrease of kidney function with aging and arteriosclerosis in hemodialysis patients. Moreover, infection, vascular puncture, and hemostasis may be related to the increase in serum Cu/Zn-SOD levels. As it is associated with numerous factors in hemodialysis patients, Cu/Zn-SOD may serve as a complex marker for arteriosclerosis, vascular, and inflammatory conditions. It is important to investigate various agents that decrease serum Cu/Zn-SOD levels to improve the life-span of hemodialysis patients.
文摘AIM: To investigate the effects of hydrogen(H2) on Cu, Zn superoxide dismutase(SOD1) activation in a rat model of corneal alkali burn. METHODS: In each rat, one cornea was subjected to alkali exposure. Physiological saline(saline group) or H2-dissolved saline(H2 group) was instilled continuously on the cornea for 5 min before and after alkali exposure. Inflammatory cells, neovascularization, and cytoplasmic SOD1 levels were evaluated immunohistochemically in enucleated eyes from both groups. Three-dimensional ultrastructural tissue changes in the eyes were analyzed using low-vacuum scanning electron microscopy.RESULTS: The numbers of both inflammatory and vascular endothelial cells were significantly reduced in the corneas of the H2 group(P<0.01). Furthermore, H2 treatment increased both cytoplasmic SOD1 levels(P<0.01) and activity in corneal epithelial cells(P<0.01). Notably, the SOD1 activity level in the H2 group was approximately 2.5-fold greater than that in the saline group.CONCLUSION: H2 treatment suppresses inflammation and neovascularization in the injured cornea and indirectly suppresses oxidative insult to the cornea by upregulating the SOD1 enzyme protein level and activity.
基金Supported by University Grants Commission,New Delhi(F.403(M/S)/2009(SA-Ⅲ/MANF)
文摘Objective:To determine the activity of superoxide dismutase(SOD) in the male and female haematophagous caprine worms,Haemonchus contortus infecting Capra hircus,and their E/S products and also to analyse the effect of Haemonchus infection on the level of host SOD.Methods:The SOD activity was analysed by using the pyrogallol autoxidation assay and non-denaturing polyacrylamide gel electrophoresis followed by specific enzyme staining by riboflavin-nitroblue tetrazolium method.Results:The adult females were found to have higher enzyme activity than the male worms.Appreciable amount of SOD activity was also detected in the worm culture medium and female worms secreted more SOD in comparison to the male parasites.The SOD activity was negatively correlated to the worm burden.Statistically significant decrease in SOD activity(P<0.05) was observed in the heavily infected host tissue in comparison to the control non-infected host tissue.SOD profile of the crude extracts of both the sexes revealed polymorphism and a fast migrating activity band being characteristic of E/S products.The SOD activities were found highly sensitive to potassium cyanide indicating the Cu/Zn form of SOD.Conclusions:Haemonchus contortus is a key model parasite for drug and vaccine discovery.The presences of SOD activity in appreciable amount in the parasite as well as its E/S products indicate that it has a well-developed active antioxidant system to protect itself from the host immune attack.SOD could be the target for vaccine development which is the need of the hour as mass drug administration for parasite control has resulted in anthelmintic resistance across the globe and threatens the viability of sheep and goat industry in many regions of the world.The infection with Haemonchus causes a drastic reduction in SOD activity of the host tissue thus effecting its protective potential.One characteristic SOD band was found in the females which was not present in any other preparations and thus could be exploited for further studies on diagnostic/control measures.
基金overseas returned scholars’ starting working grants to AN Zhi-gang (Northeast Forestry University)
文摘The expression of a rice Cu/Zn superoxide dismutase （Cu/Zn-SOD） in Saccharomyces cerevisiae regulated by GAPDH promoter, involved in the inhibition of endogenous Glutathione （GSH） synthesis, and the competitive expression was detected by constructing the expression vector transferred Cu/Zn-SOD gene into wild-type S. cerevisiae. Transcription and expression of the Cu/Zn-SOD gene in S. cerevisiawere were confirmed by northern blot and SDS-PAGE, respectively, and activity of the Cu/Zn-SOD from crude extracts was enzymatically detected based on the effect of nitroblue tetrazolium （NBT） after running a native polyacrylamide gel. The GSH synthesis was also tested by DTNB （5, 5＇-Dithiobis （2-nitrobenzoic acid）） method. Results showed that GSH synthesis was evidently suppressed by the expression of Cu/Zn-SOD gene in both control and heat shock strains. It implied that the expression of the Cu/Zn-SOD gene in S. cerevisiae has more potential facility in response to oxidative exposure than that of endogenous GSH, although Cu/Zn-SOD and GSH were both contributed to the function of oxygen radical oxidoreduction.
文摘目的 单原子纳米酶(single-atom nanozyme,SAN)因其高原子利用率及丰富的类酶活性被广泛研究。但是目前大多数SAN活性位点负载量较低,限制了其进一步应用和发展。本研究旨在制备一种高原子负载量的SAN,并对其类酶活性进行系统研究,希望为高负载SAN的制备提供思路,并为SAN在更广泛领域的应用提供理论支持。方法 本研究通过原位锚定策略将金属盐前驱体锚定在氨基化石墨烯量子点框架中,在惰性气体保护下进行高温热解稳定Cu原子和载体之间的化学键,制备出负载量高达7.66%(质量百分比)的高负载Cu单原子纳米酶(high-loading Cu SAN)。此外,以3,3’,5,5’-四甲基联苯胺(TMB)和氮蓝四唑(NBT)为显色剂,评估了high-loading Cu SAN的类过氧化物酶(POD)、类氧化物酶(OXD)及类超氧化物歧化酶(SOD)活性,并与传统金属有机框架锚定法制备的低负载Cu单原子纳米酶(low-loading Cu SAN)作比较。以过氧化氢(H_(2)O_(2))为催化底物,对比研究了高/低负载Cu SAN的类过氧化氢酶(CAT)活性。结果 研究表明,本文制备的高负载Cu SAN的类POD和SOD活性分别是低负载Cu SAN的3.4倍和8.88倍,且表现出类酶催化选择性。结论 本研究为高负载SAN的制备和活性研究提供了思路,为SAN在检测传感、疾病治疗以及环境保护等方面的应用奠定了基础。
基金This work was supported by Grants-in-Aid 16H04768 for Scientific Research(B)(to YF)and 19H05765 for Scientific Research on Innovative Areas(to YF)from the Ministry of Education,Culture,Sports,Science and Technology of Japan and also supported by the Pharmacological Research Foundation,Tokyo(to ET).
文摘Amyotrophic lateral sclerosis(ALS)is characterized by adult-onset progressive degeneration of upper and lower motor neurons.Increasing numbers of genes are found to be associated with ALS;among those,the first identified gene,SOD1 coding a Cu/Zn-superoxide dismutase protein(SOD1),has been regarded as the gold standard in the research on a pathomechanism of ALS.Abnormal accumulation of misfolded SOD1 in affected spinal motor neurons has been established as a pathological hallmark of ALS caused by mutations in SOD1(SOD1-ALS).Nonetheless,the involvement of wild-type SOD1 remains quite controversial in the pathology of ALS with no SOD1 mutations(non-SOD1 ALS),which occupies more than 90%of total ALS cases.In vitro studies have revealed post-translationally controlled misfolding and aggregation of wild-type as well as of mutant SOD1 proteins;therefore,SOD1 proteins could be a therapeutic target not only in SOD1-ALS but also in more prevailing cases,non-SOD1 ALS.In order to search for evidence on misfolding and aggregation of wild-type SOD1 in vivo,we reviewed pathological studies using mouse models and patients and then summarized arguments for and against possible involvement of wild-type SOD1 in non-SOD1 ALS as well as in SOD1-ALS.
基金Project supported by the National Basic Research Program of China （No.2003CB 114400） and the National Natural Science Foundation of China （Nos. 30100035 and 30570383）.
文摘To investigate whether the proton-accepting ability of imidazole in Cu,Zn-superoxide dismutase （SOD） was possibly modulated by Zn（Ⅱ） or not, the proton affinity （Ap） of N^3 in imidazole group was calculated by density functional theory （DFT） with B3LYP functional. It was found that Zn（Ⅱ） attenuates the Ap, because of its electron-withdrawing effect, while the three ligands connected with Zn（Ⅱ） （residues of two His and one Asp） exert an opposite effect, owing to their electron-donating ability. This finding suggested that the three ligands should play a role in the normal function of Cu,Zn-SOD and should be taken into consideration in the future study.
文摘When a protein is encapsulated into poly( DL -lactide-co-glycolide)(PLGA) microspheres by means of the double-emulsion method,the harsh microspheres formation process including ultrasonification,exposure to an organic solvent and a polymer may cause the denaturation of the protein. In this study,we investigated the enzymatic activity change and the effect of the excipients on the stability of recombinant human Cu,Zn-superoxide dismutase(rhCu,Zn-SOD) during the emulsification. The specific activity recovery was found to be concentration dependent and the excipients involved such as PEG 600 and Tween 20,and trehalose were shown to increase the stability of rhCu,Zn-SOD. The protein structural integrity within the microspheres was analyzed by FTIR. The structure of rhCu,Zn-SOD within PLGA microspheres containing trehalose was found to be similar to that of the native solid state,whereas the protein encapsulated during the preparation in the absence of any excipient changed due to the possible hydrophobic interaction with the polymer. The results suggest that a rational stability strategy for protein to be encapsulated into microspheres should aim at different processes.
